U.S. patent application number 12/992463 was filed with the patent office on 2011-12-15 for polyamide emulsifier based on polyamines and fatty acid/carboxylic acid for oil based drilling fluid applications.
Invention is credited to Thomas William Himmel, Alan Duncan James, Jon B. Staley, Dale Stanley Steichen, Hua Yu.
Application Number | 20110306523 12/992463 |
Document ID | / |
Family ID | 40042730 |
Filed Date | 2011-12-15 |
United States Patent
Application |
20110306523 |
Kind Code |
A1 |
Yu; Hua ; et al. |
December 15, 2011 |
Polyamide Emulsifier Based on Polyamines and Fatty Acid/Carboxylic
Acid for Oil Based Drilling Fluid Applications
Abstract
The present invention generally relates to emulsifiers for
oil-based drilling fluids and muds comprising an emulsifier based
on the polyamides derived from fatty acid/carboxylic acid and
optionally alkoxylated polyamines. The invention also relates to
oil or synthetic based drilling fluids comprising the emulsifiers
of the invention and to drilling methods utilizing same.
Inventors: |
Yu; Hua; (Scarsdale, NY)
; Steichen; Dale Stanley; (Danbury, CT) ; James;
Alan Duncan; (Hopewell Junction, NY) ; Staley; Jon
B.; (Rolling Meadows, IL) ; Himmel; Thomas
William; (Naperville, IL) |
Family ID: |
40042730 |
Appl. No.: |
12/992463 |
Filed: |
May 12, 2009 |
PCT Filed: |
May 12, 2009 |
PCT NO: |
PCT/EP09/55684 |
371 Date: |
January 6, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61053493 |
May 15, 2008 |
|
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Current U.S.
Class: |
507/131 ;
554/37 |
Current CPC
Class: |
C08G 73/028 20130101;
C08L 91/005 20130101; C08L 91/00 20130101; C08L 91/00 20130101;
C09K 8/36 20130101; C08L 91/005 20130101; C08L 79/02 20130101; B01F
17/005 20130101; C08L 91/00 20130101; C08L 2666/20 20130101; C08L
77/00 20130101; C08L 79/02 20130101; C08L 77/00 20130101 |
Class at
Publication: |
507/131 ;
554/37 |
International
Class: |
C09K 8/34 20060101
C09K008/34; C07C 231/02 20060101 C07C231/02; C07C 237/10 20060101
C07C237/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 26, 2008 |
EP |
08159130.7 |
Claims
1. A compound of formula (A)
Y{O(CH.sub.2).sub.e}.sub.a{NX(CH.sub.2).sub.e}.sub.b{N[C(O)R.sup.2](CH.su-
b.2).sub.e}.sub.c{NH(CH.sub.2).sub.e}.sub.dNHZ (A) wherein a is an
integer of from 0-5, b and c are each independently selected from
integers of from 0 to 10, with the proviso that b and c cannot both
be 0 at the same time, d is an integer of from 0 to 10, e is an
integer of from 1-5, Y is selected from H, X, --C(O)R.sup.1 or
--C(O)R.sup.2 and Z is selected from --C(O)R.sup.1 or X, wherein
R.sup.1 and R.sup.2 are linear or branched, saturated or
unsaturated hydrocarbyl groups having from 7 to 30 carbon atoms,
and X is a carbonyl group derived from an acid comprising a
C.sub.2-C.sub.10 hydrocarbon chain, said acid being selected from
the group consisting of monocarboxylic acids, dicarboxylic acids,
tricarboxylic acids and mixtures thereof.
2. The compound of claim 1 wherein R.sup.1 and R.sup.2 are derived
from a fatty acid source, wherein said fatty acid source is chosen
from coconut, mustard seed, palm, palm kernal, soybean, tallow,
tall oil, rape seed, and mixtures thereof.
3. The compound according to claim 1 wherein X is a carbonyl group
derived from a carboxylic acid chosen from the group consisting of
formic acid, acrylic acid, amino acid, malic acid (anhydrate),
succinic acid, glutaric acid, adipic acid, lactic acid, citric acid
and mixtures thereof.
4. The compound of claim 1 wherein said compound is a alkoxylated
polyamide of the formula:
H{OCH.sub.2CH.sub.2}.sub.a{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2-
H]CH.sub.2CH.sub.2}.sub.b{N[C(O)R.sup.2]CH.sub.2CH.sub.2}.sub.c{NHCH.sub.2-
CH.sub.2}.sub.dNHC(O)R.sup.1 where R.sup.1 and R.sup.2 are each
independently selected from linear or branched, saturated or
unsaturated C.sub.10-C.sub.24 hydrocarbyl groups.
5. The compound of claim 1, having the formula:
H{OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2H]CH.s-
ub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.sub.2CH.sub-
.2}.sub.dNHC(O)R.sup.1 wherein R.sup.1=R.sup.2 and being selected
from the group consisting of C.sub.17 hydrocarbyl group derived
from tall oil, C.sub.21 hydrocarbyl group derived from erucic acid,
C.sub.17 hydrocarbyl group derived from oleic acid, C.sub.17
hydrocarbyl group derived from soybean oil; b is 0-4; c is 0 to 4,
with the proviso that b and c cannot both be 0 at the same time;
and d is 0 or 2.
6. The compound of any of the claim 1, having the formula:
R.sup.3C(O){OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.s-
ub.2H]CH.sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.s-
ub.2CH.sub.2}.sub.dNHC(O)R.sup.1 wherein R.sup.1=R.sup.2=R.sup.3
and being selected from the group consisting of C.sub.17
hydrocarbyl group derived from tall oil and C.sub.21 hydrocarbyl
group derived from erucic acid; b is 0-4; c is 0 to 4, with the
proviso that b and c cannot both be 0 at the same time; and d is 0
or 2.
7. A drilling fluid composition which comprises at least one oil
and at least one polyamide compound according to claim 1.
8. The composition of claim 7 wherein said composition comprises
from 0.5 to 4 wt % of said at least one polyamide, based on the
total weight of the composition.
9. A process of preparing the polyamide compound of claim 1, said
process comprising reacting a fatty acid and an polyamine to form
an amidoamine intermediate product followed by further reacting
said amidoamine intermediate with a C.sub.2-C.sub.10 mono-,
di-rboxylic acid, or tricarboxylic acid containing C.sub.2 to
C.sub.10 hydrocarbyl groups, or a mixture of such acids in order to
obtain said polyamide compound.
10. The process of claim 9 wherein the mole ratio of said fatty
acid to said amine is from about 0.1:1 to about 10:1, and the molar
ratio of said amidoamine intermediate and said monocarboxylic acid,
dicarboxylic acid, or tricarboxylic acid containing C.sub.2 to
C.sub.10 alkyl/alkylene groups, is from about 0.2:1 to 5:1.
11. The process of claim 9 wherein said fatty acid is of the
formula: R--C(O)OH wherein R is a saturated or unsaturated,
branched or straight chain, substituted or unsubstituted
hydrocarbyl group having from 7 to 30 carbon atoms, and said
alkoxylated polyamine is of the formula:
H{O(CH.sub.2).sub.e}.sub.a[NH(CH.sub.2).sub.e].sub.fNH.sub.2
wherein a is 0 or 1, e is 2 or 3 and f is 1-4.
12. The process of claim 9 wherein said polycarboxylic acid is
chosen from the group consisting of formic acid, acrylic acid,
amino acid, malic acid (anhydrate), succinic acid, glutaric acid,
adipic acid, lactic acid, citric acid and mixtures thereof.
13. The process of claim 9 wherein in a first step the fatty acid
is reacted with said alkoxylated polyamine is reacted with said
fatty acid at an equivalent ratio of from about 0.2:1 to about 2:1,
at a temperature of from about 150.degree. C. to 175.degree. C.
until the acid is reduced to less than about <0.2 meq/g, in
order to obtain said polyamine intermediate and in a second step
the polyamine intermediate is reacted with said carboxylic acid at
an equivalent ratio of from about 0.1:1 to 1:1 at a temperature of
from about 50 to 150.degree. C. until amine number falls below
about 0.5 meq/g) and acid number is less than about 1.5 meq/g.
14. A method of emulsifying an oil based drilling fluid composition
which comprises adding to said composition from 0.5 to 4 wt % of
said at least one compound according to claim 1.
15. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention generally relates to emulsifiers for
oil-based drilling fluids and muds based on the polyamides derived
from fatty acid/carboxylic acid and polyamines. The invention also
relates to oil or synthetic based drilling fluids comprising the
emulsifiers of the invention and to drilling methods utilizing
same.
BACKGROUND OF THE INVENTION
[0002] A drilling fluid or mud is a specially designed fluid that
is circulated through a wellbore as the wellbore is being drilled
to facilitate the drilling operation. Drilling fluids facilitate
the removal of drill cuttings from the wellbore, cool and lubricate
the drill bit, aid in supporting the drill pipe and drill bit, and
provide a hydrostatic head to maintain the integrity of the
wellbore walls thereby minimizing the potential for well blowouts.
Specific drilling fluid systems are selected to optimize a drilling
operation in accordance with the characteristics of a particular
geological formation.
[0003] Oil or synthetic-based mud, or invert emulsions, are
normally used to drill swelling or sloughing shale, salt, gypsum,
anhydrite or other evaporate formations, hydrogen
sulfide-containing formations, and hot (greater than about
300.degree. F.) holes, but may be used in other holes penetrating a
subterranean formation as well. This class of drilling fluids
typically contains oil or a synthetic oil or other synthetic
material or synthetic fluid ("synthetic") as the continuous phase
and may also contain water which is dispersed in the continuous
phase by emulsification so that there is no distinct layer of water
in the fluid. The term "oil mud" or "oil or synthetic-based mud"
typically means an invert oil mud emulsion or invert emulsion. An
all oil mud simply comprises 100% oil by volume as the liquid
phase; that is, there is no aqueous internal phase. An invert
emulsion drilling fluid may commonly comprise between about 50:50
to 95:5 by volume oil phase to water phase.
[0004] Invert emulsions used in drilling typically comprise: a base
oil or synthetic fluid for the external phase; a saline, aqueous
solution for the internal phase (typically a solution comprising
about 30% calcium chloride); and other agents or additives for
suspension, fluid loss, density, oil-wetting, emulsification,
filtration, and rheology control.
[0005] U.S. Pat. No. 7,247,604 generally relates to alkanolamide
based emulsifiers obtained by transamidification of fatty acid
esters and mono-alcohols or oils of a plant of animal origin
(triglyceride) with alkanoamine. The oil based drilling fluid made
with the emulsifier and co-surfactant was claimed having
temperature-stable, non-toxic to the environment, and high
temperature and high pressure (HTHP) well drilling, completion or
workover application properties.
[0006] U.S. Pat. Nos. 4,508,628 and 4,575,428 disclose invert
emulsion drilling fluid emulsfiers derived from polyamines. The
preferred polyamide emulsifiers are prepared by first reacting a
polyamine with fatty acid in order to form a amidoamine and
thereafter reacting the amidoamine intermediate with a dicarboxylic
acid (in U.S. Pat. No. 4,508,628) or tricarboxylic acid (in U.S.
Pat. No. 4,575,428). It is apparent from the disclosure of the
documents that short chain polyamines containing no alkoxy groups
are contemplated.
[0007] U.S. Pat. No. 3,169,113 discloses emulsifiers for
water-in-oil acidic fracturing fluids. The disclosed emulsifier has
two components: (a) a 9-18 carbon monocarboxylic acid fatty acid
salt of a partial amide of a polyalkyllene polyamine with 2-6
carbon alkylene groups and 3-5 amino nitrogens in which at least
two amino groups are amidified with 9-18 carbon monocarboxylic
fatty acids and wherein there is at least one nonamidified amino
group forming a salt with the acid and, (b) a polyamide of an
alkylene polyamine with 2-6 carbon alkylene groups and 2-5 amino
nitrogens and a 9-18 carbon monocarboxylic fatty acid.
[0008] U.S. Pat. No. 4,501,672 discloses fluid loss reducing
additives for oil-based working fluids. The additive is obtained by
reacting 1 mole of dialkylene triamine with 2 moles of fatty acid.
Example 1 specifically covers the bridging of diethylenetriamine
dioleylamide with maleic anhydride.
[0009] WO 89/11516 discloses oil-based emulsifiers for drilling
fluids that are the reaction product of one or two moles of an
amide-amine or a hydroxylalkylamide with one to five moles of a
dicarboxylic acid or an acid anhydride. Starting on page 5 of this
document it is apparent that the use of short chain polyamines with
no alkoxy groups is contemplated.
[0010] U.S. Pat. No. 4,658,036 discloses an invert emulsion and a
process of preparing same. The emulsifiers are prepared by reacting
at least one tall oil fatty acid with acrylic acid, maleic
anhydride, or fumaric acid, followed by reaction with
diethylenetriamine and at least one tall oil fatty acid in order to
give the invert emulsifier.
[0011] With space at some well sites limited, such as on offshore
platforms, and with increasing costs of transport of materials to a
well site, there is industry-wide interest, on-going need for more
efficient and concentrated drilling fluid additives and for
drilling fluids which can be formulated and maintained with fewer
additives in lesser amounts than commonly utilized with prior art
drilling fluids.
SUMMARY OF THE INVENTION
[0012] One object of the present invention is thus to provide a
drilling fluid additive that can at least partly meet the above
mentioned need in the art.
[0013] The present inventors have surprisingly found that certain
polyamides which are derived from fatty acid/carboxylic acid and
optionally alkoxylated polyamides are very efficient as emulsifiers
for oil-based drilling fluids and muds.
[0014] Hence, in a first aspect, the present invention relates to a
polyamide compound according to the appended claims.
[0015] Conventional emulsifiers for oil-based mud will usually
degrade under high-temperature and pressure conditions, which leads
to the deterioration of the oil-based mud. This requires that more
emulsifier be put into the mud system in order to maintain the
desired properties, which can substantially increase the cost of
the system. The emulsifier of the present invention is much more
effective under high temperature and high pressure conditions thus
reducing the amount of additional emulsifier required to emulsify
the system, thereby improving the performance and cost of the
system.
[0016] In a third aspect, the present invention relates to a
drilling fluid composition comprising an oil and at least one such
polyamide compound.
[0017] In a third aspect, the present invention relates to a
process for the manufacture of such polyamide compounds.
[0018] In a fourth aspect, the present invention relates to the use
of such polyamide compounds as emulsifiers for oil based drilling
fluids.
These and other aspects of the present invention will be further
described in the following detailed description of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The polyamides of the invention are derived from fatty
acid/carboxylic acid and optionally alkoxylated polyamines. They
provide emulsification and allow concentrated products, either
solids or liquids, with superior properties. Conventional
emulsifiers for oil-based mud will usually degrade under
high-temperature and pressure conditions, which leads to the
deterioration of the oil-based mud. This requires that more
emulsifier be put into the mud system in order to maintain the
desired properties, which can substantially increase the cost of
the system. The emulsifier of the present invention is much more
effective under high temperature and high pressure conditions thus
reducing the amount of additional emulsifier required to emulsify
the system, thereby improving the performance and cost of the
system.
[0020] The polyamide emulsifiers of the invention can generally be
represented by formula (A)
Y{O(CH.sub.2).sub.e}.sub.a{NX(CH.sub.2).sub.e}.sub.b{N[C(O)R.sup.2](CH.s-
ub.2).sub.e}.sub.c{NH(CH.sub.2).sub.e}.sub.dNHZ (A)
[0021] wherein a is an integer of from 0-5, in another embodiment 0
to 2, b and c are each independently selected from integers of from
0 to 10, with the proviso that b and c cannot both be 0 at the same
time, d is from 0 to 10, e is an integer of from 1-5, Y is selected
from H, X, C(O)R.sup.1 or C(O)R.sup.2 and Z is selected from
C(O)R.sup.1 or X, where R.sup.1 and R.sup.2 are linear or branched,
saturated or unsaturated alkylene groups, and X is a carbonyl group
derived from a monocarboxylic acid, dicarboxylic acid, or
tricarboxylic acid containing a C.sub.2 to C.sub.10 hydrocarbon
group, such as a alkyl and/or alkylene, or a mixture of such acids.
One of ordinary skill in the art would recognize that various
polycarboxylic acids could be utilized including, but not limited
to formic acid, acrylic acid, amino acid, malic acid (anhydrate),
succinic acid, glutaric acid, adipic acid, lactic acid, citric acid
and the like, and mixtures thereof.
[0022] In embodiments of the invention, a is typically an integer
from 0 to 5, such as from 0 to 2, for example 0 to 1, such as
1.
[0023] Each of b and c are typically independently selected from an
integer of from 0 to 10, such as 0 to 4, such as 0 to 3, with the
proviso that b and c cannot both be 0 at the same time.
[0024] Typically, d is from 0 to 10, such as from 0 to 4.
[0025] In each instance, e is typically independently from 1 to 5,
such as from 2 to 4.
[0026] R.sup.1 and R.sup.2 are same or different and are selected
from linear or branched, saturated or unsaturated C.sub.7 to
C.sub.30, such as C.sub.10 to C.sub.24, such as C.sub.16 to
C.sub.22, hydrocarbyl groups, such as alkyl or alkenyl groups.
Typically R.sup.1 and R.sup.2 each is a linear alkyl or mono- or
polyunsaturated linear alkenyl.
[0027] In one embodiment, a is 0 to 1, each of b and c are
independently selected from an integer of from 0 to 3, with the
proviso that b and c cannot both be 0 at the same time, d is
selected from 0 to 2, e is from 2 to 4, and R.sup.1 and R.sup.2 are
each independently selected from linear or branched, saturated or
unsaturated C.sub.16-C.sub.22 hydrocarbyl groups.
[0028] R.sup.1 and R.sup.2 are typically derived from a fatty acid
source. Fatty acids typically has the general formula R--COOH,
where R, which represents R.sup.1 and/or R.sup.2 in formula A.
Typically, R is a saturated (alkyl) or mono or polyunsaturated
(alkenyl) C.sub.7 to C.sub.30 hydrocarbon. Fatty acid sources
include, but are not limited to coconut, mustard seed, palm, palm
kernal, soybean, tallow, tall oil, rape seed, safflower, sunflower
and mixtures thereof. Fatty acid sources, such as vegetabilic and
animalic sources typically each provide a mixture of fatty acids of
different lengths. In embodiments of the invention, the fatty acid
source is selected from tall oil, rape seed, mustard seed and
mixtures thereof.
[0029] Fatty acids R--COOH from which R.sup.1 and R.sup.2 are
derived from include, but are not limited to caprylic, decanoic,
lauric, myristic, palmitic, heptadecanoic, stearic, arachidic,
behenic, lignoceric, linolenic, stearidonic, eicosapentaenoic,
docosahexaenoic, arachidonic, oleic, elaidic, erucic and nervonic
acids.
[0030] Tall oil or rape seed fatty acids are particularly preferred
fatty acid sources for use in the process for making the polyamide
emulsifier of the present invention.
[0031] Fatty acids from tall oil includes, but are not limited to
palmitic acid, oleic acid and linoleic acid, while fatty acids from
rape seed oil includes, but are not limited to, erucic acid.
[0032] In another embodiment, the polyamide emulsifier of the
invention is represented by the formula:
H{OCH.sub.2CH.sub.2}.sub.a{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.-
2H]CH.sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c{NHCH.sub.2C-
H.sub.2}.sub.dNHC(O)R.sup.1
where R.sup.1 and R.sup.2 are each independently selected from
linear or branched, saturated or unsaturated hydrocarbyl groups. In
another embodiment, R.sup.1 and R.sup.2 are each independently
selected from linear or branched, saturated or unsaturated
C.sub.10-C.sub.24 hydrocarbyl groups. As mentioned above, R.sup.1
and R.sup.2 can be derived from a fatty acid source such as tall
oil, rape seeds, mustard seeds and/or mixtures thereof and the
like. In this embodiment, X substituent of general formula (A) is a
carbonyl group derived from citric acid, as is apparent from the
above formula.
[0033] In another embodiment, the polyamide emulsifier of the
invention is chosen from at one or more polyamides of the following
formulae:
H{OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2H]CH.-
sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.sub.2CH.su-
b.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=C.sub.17 hydrocarbyl group derived from
tall acid; and b is 0 to 4, c is 0 to 4, with the proviso that b
and c cannot both be 0 at the same time, and d is 0 to 4, and in
another embodiment, b is 0 to 3, c is 0 to 3, with the proviso that
b and c cannot both be 0 at the same time, with the proviso that b
and c cannot both be 0 at the same time, and d is 0 or 2;
H{OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2H]CH.-
sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.sub.2CH.su-
b.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=C.sub.21 hydrocarbyl group derived from
erucic acid; and b is 0 to 4, c is 0 to 4, with the proviso that b
and c cannot both be 0 at the same time, and d is 0 to 4, and in
another embodiment, b is 0 to 3, c is 0 to 3, with the proviso that
b and c cannot both be 0 at the same time, and d is 0 or 2;
H{OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2H]CH.-
sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.sub.2CH.su-
b.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=C.sub.17 hydrocarbyl group derived from
oleic acid; and b is 0 to 4, c is 0 to 4, with the proviso that b
and c cannot both be 0 at the same time, and d is 0 to 4, and in
another embodiment, b is 0 to 3, c is 0 to 3, with the proviso that
b and c cannot both be 0 at the same time, and d is 0 or 2;
H{OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.sub.2H]CH.-
sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.sub.2CH.su-
b.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=C.sub.17 hydrocarbyl group derived from
soybean oil, such as the hydrocarbyl derived from .alpha.-linolenic
acid; and b is 0 to 4, c is 0 to 4, with the proviso that b and c
cannot both be 0 at the same time, and d is 0 to 4, and in another
embodiment, b is 0 to 3, c is 0 to 3, with the proviso that b and c
cannot both be 0 at the same time, and d is 0 or 2;
R.sup.3C(O){OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.-
sub.2H]CH.sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.-
sub.2CH.sub.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=R.sup.3=C.sub.17 hydrocarbyl group derived
from tall oil, such as the hydrocarbyl derived from oleic acid
and/or linoleic acid; and b is 0 to 4, c is 0 to 4, with the
proviso that b and c cannot both be 0 at the same time, and d is 0
to 4, and in another embodiment, b is 0 to 3, c is 0 to 3, with the
proviso that b and c cannot both be 0 at the same time, and d is 0
or 2; and
R.sup.3C(O){OCH.sub.2CH.sub.2}{N[C(O)CH.sub.2C(OH)(CO.sub.2H)CH.sub.2CO.-
sub.2H]CH.sub.2CH.sub.2}.sub.b{NC(O)R.sup.2CH.sub.2CH.sub.2}.sub.c--{NHCH.-
sub.2CH.sub.2}.sub.dNHC(O)R.sup.1
wherein R.sup.1=R.sup.2=R.sup.3=C.sub.17 hydrocarbyl group derived
from erucic acid; and b is 0 to 4, c is 0 to 4, with the proviso
that b and c cannot both be 0 at the same time, and d is 0 to 4,
and in another embodiment, b is 0 to 3, c is 0 to 3, but b and c
can't be 0 at the same time, and d is 0 or 2.
[0034] The emulsifier of the invention is highly effective with low
dosage use, and when used in a typical oil-based drilling fluid
formulation, produces a drilling fluid with high electric stability
and excellent rheology before and after aging. Additionally, there
is no need to add lime to the mud system in order to activate the
emulsifier of the invention, i.e., the emulsifier of the invention
can be utilized without the use of lime. In one embodiment, the
emulsifier of the invention is lime free. The emulsifier of the
invention also has low fluid loss (filtration properties) at high
temperature and pressure using relatively low dosages, without the
necessity of utilizing other fluid loss or filtration
additives.
[0035] The polyamide emulsifier of the invention is generally
prepared from the condensation reaction between fatty acids (I) and
optionally alkoxylated polyamines (II). The fatty acids and
optionally alkoxylated polyamines are reacted in such proportion as
to create an optionally alkoxylated amidoamine intermediate product
(III) having 1 equivalent of primary plus secondary amines (N--H
bonds) in optionally alkoxylated polyamine (II) reacts with 0.2 to
2.0 equivalents of carboxylic acid in fatty acid (I). The preferred
ratio is 0.3 to 1.5 eq of carboxylic acids, and the most preferred
is 0.4 to 1 eq. Then, 1 eq of N--H bonds in optionally alkoxylated
amidoamine intermediate (III) is further reacted with 0.01 to 2.0
eq of carboxylic acids in a monocarboxylic acid, dicarboxylic acid,
or tricarboxylic acid containing C.sub.2 to C.sub.10 alkyl/alkylene
groups, or a mixture of such acids at 0.01 to 2.0 eq of carboxylic
acids, in another embodiment from about 0.2 to 1.5 eq of carboxylic
acids in order to get the optionally alkoxylated polyamide
emulsifier of the present invention (V). By optionally alkoxylated
polyamine/polyamide etc is meant a polyamine/polyamide etc that may
or may not be alkoxylated. With references to formula A above, the
polyamide compound is alkoxylated if a is other than 0. Citric acid
(IV) is exemplified in the reaction below.
##STR00001##
[0036] The fatty acids (II) employable in the preparative reaction
are generally selected from fatty acids of the formula: R--C(O)OH
wherein R is a saturated or unsaturated, branched or straight
chain, substituted or unsubstituted hydrocarbyl group having from 7
to 30 carbon atoms.
[0037] The polyamines employable in the aforementioned process
include, but are not limited to those represented by the
formula:
H{O(CH.sub.2).sub.e}.sub.a[NH(CH.sub.2).sub.e].sub.fNH.sub.2 where
a=0 or 1; e=2 or 3, and f=1 to 4
Alkoxylated polyamines, alkoxylated fatty polyamine, alkoxylated
diamines, including mono- or dialkyl symmetrical or asymmetrical
ethylene diamines, alkoxylated propane diamines, polyamine analogs
of the above, and mixtures and combinations thereof are examples of
those polyamines useful in the above process. Suitable commercial
alkoxylated polyamines are, for example, Berolamine 10 and
Berolamine 20. Berolamine 20 is a mixture of approx. 55% of
ethylenepolyamines (isomers of TETA, TEPA, PEHA, and higher) and
approx. 45% of N-ethanol derivatives of polyalkylenepolyamines, and
are commercially available from Akzo Nobel Functional Chemicals
bv.
[0038] One of ordinary skill in the art would recognize that
various mono and polycarboxylic acids could be utilized in the
described process including, but not limited to formic acid,
acrylic acid, amino acid, malic acid (anhydrate), succinic acid,
glutaric acid, adipic acid, lactic acid, citric acid and the like,
and mixtures thereof. In one embodiment, citric acid is the
carboxylic acid of choice.
[0039] In the first step of the reaction, 1 equivalent of primary
plus secondary amines (N--H bonds) in Berolamine 20 reacts with 0.2
to 2.0 equivalents of carboxylic acid in a tall oil or rapeseed oil
fatty acid to form an intermediate. The preferred ratio is 0.3 to
0.9 eq of carboxylic acids, and the most preferred is 0.4 to 0.8
eq. In the second step, 1 eq of N--H bonds in the intermediate
react with 0.5 to 2.0 eq of carboxylic acids in citric acid. More
preferred is 0.75 to 1.5 eq of carboxylic acids in citric acid.
[0040] The reaction temperature of the first step is generally from
150.degree. C. to 175.degree. C., preferably about 165.degree. C.
and is generally run for about 2-10 hrs until acid is reduced to
less than about <0.2 meq/g. The second step is generally carried
out at temperatures of between 50 and 150.degree. C. for 2 to 3 hrs
until amine number falls below about 0.5 meq/g) and acid number is
less than 1.5 meq/g. A small amount of mineral oil based solvent is
used during the second step reaction for lower viscosity and better
mixing property. Use of a catalyst is not required in either step
of the reaction.
[0041] Side products from the reactions above include, but are not
limited to the esters between fatty acids and/or the carboxylic
acid employed, e.g., citric acid and alkoxylated polyamines
(polyamides), and the imidazolines, etc.
[0042] The emulsifier of the invention is typically formulated with
base oils (diesel or mineral or polyolefin) and polyol or polyol
ether(s) based additives to control the activity and flowability,
especially at low temperature. These additives include, but are not
limited to ethylene glycol, propylene glycol, diethylene glycol,
dipropylene glycol, ethylene glycol butyl ether, diethylene glycol
butyl ether, triethylene glycol butyl ether, etc.
[0043] The emulsifier of the invention is a superior additive for
oil or synthetic based drilling fluids, affording enhanced
emulsification, and improved electrical stability and fluid loss
control, with significantly less volume of additive than previously
known with prior art drilling fluid additives. The emulsifier of
the invention effects satisfactory emulsification at addition rates
typically about one-third the quantity commonly needed for
emulsification of oil or synthetic based fluids with prior art
emulsifiers. Typically, three pounds to about five pounds of the
emulsifier of the invention per barrel of drilling fluid can be
effective for emulsification. Even lower quantities can improve the
electrical stability and filtration control of drilling fluids,
even if already emulsified with other emulsifiers.
[0044] Typically, anywhere between about 0.2 to 4 wt % of polyamide
compound(s) of the invention is employed in drilling fluid
compositions, in another embodiment, between about 0.3 to 3 wt % is
employed. Typical oil based drilling fluids containing the
emulsifier of the invention are based on oils (diesel or mineral or
polyolefin), and may also contain components such as organoclay,
brine, weighting agents, limes, dispersants, stabilizers, and
barite. Additional components are well within the knowledge of one
of ordinary skill in the art.
[0045] The emulsifier of the invention is highly active and is
believed to be useful with all or substantially all synthetic and
oil-based systems known to be effective for drilling fluids. The
emulsifier of the invention may also impart a higher viscosity to
the drilling fluid and thus is preferably added to the base
drilling fluid before any weighting agents are added.
[0046] The present emulsifier operates efficiently at high
temperatures and pressures, and is stable even at temperatures up
to about 500.degree. F. without filtration additives and up to
about 500.degree. F. with filtration additives. Adding wetting
agents along with the product of the invention in an emulsifier
package may improve the oil-wetting nature of the drilling fluid in
some base oils but will not be needed in others. Wetting agents may
also improve the rheological stability at temperatures up to about
300.degree. F. and further enhance performance of some fluid
systems.
[0047] The drilling fluid composition of the invention generally
contains at least one oil or synthetic based drilling oil. Such
drilling oils are known as oil muds and are readily known to those
skilled in the art. The drilling fluid composition of the invention
also preferably includes brine. In most cases, sodium, calcium
and/or magnesium brine is employed.
[0048] A method of the invention comprises adding the present
polyamide emulsifier to an oil or synthetic based drilling fluid or
employing a drilling fluid comprising the polyamide emulsifier of
the invention in drilling a borehole in a subterranean formation.
In another embodiment, a method of the invention comprises adding
the polyamide emulsifier of the invention to an oil or synthetic
based drilling fluid to facilitate emulsification of the drilling
fluid or the formation of invert emulsions. The invention also
relates to a method of enhancing the rate of penetration while
drilling a well which comprises circulating a drilling fluid
composition according to the invention throughout a borehole while
simultaneously rotating a string of drill pipe containing a rotary
drill bit on its lower end in contact with the bottom of the
borehole, thereby facilitating the removal of drill cuttings formed
by said drill bit from the borehole, lubricating the drill bit,
removing the heat, and stabilizing the wellbore hole.
[0049] The oil or synthetic based drilling fluids of the invention
may also include one or more of a variety of optional ingredients
known to one of ordinary skill in the art. Such optional
ingredients include, but are not limited to organoclays, fluid loss
control agents, rheology modifiers, wetting agents, limes, brine,
dispersants, stabilizers, barite, and the like.
[0050] The rheology (plastic viscosity, yield point, and gel
strength) as well as fluid loss property are the two most important
attributes of a drilling fluids. Proper plastic viscosity indicates
that the drilling fluid is capable of drilling rapidly because of
the proper viscosity of drilling fluid exiting at the drilling bit.
Yield point is used to evaluate the ability of a drilling fluid to
lift drilling cuttings out of the annulus. The present emulsifier
delivers better drilling fluid emulsion stability, thus delivers
better controllable rheology of the drilling fluid under high
temperature and high pressure condition. Fluid loss is the leakage
of the liquid phase of drilling fluid to the formation matrix while
drilling. The resulting buildup of solid material or filter cake
may be undesirable, as may the penetration of filtrate through the
formation. Fluid loss can be significantly reduced by improving the
drilling fluid emulsion stability with the present emulsifier under
high temperature and high pressure conditions, and the compounds of
the present invention can thus be used to reduce loss of drilling
fluid. Besides, the electric stability and tolerance to the
contamination are also very important property of a drilling fluid,
and both properties have a close relationship with drilling fluid
emulsion stability.
[0051] The drilling fluid performance properties invention will now
be exemplified by the following non-limiting examples.
Example 1
Emulsifier Preparation
[0052] In a 2-L 5-necked flask plus Dean-Stark trap under N.sub.2,
1084.2 g of Century D-1 (available from Arizona Chemicals) and
248.8 g of Berolamine 20 (Akzo Nobel Chemicals) were placed. This
mixture was heated to 165.degree. C. for 8 hr with N.sub.2 sparge.
A total of 55.8 g of water distilled, and a sample showed 0.126
meq/g of residual acid (target.ltoreq.0.15 or 5%) and 1.874 meq/g
of free amine. After adding 400.8 g of ODC oil (Sasol North
America) to the intermediate (for 80% solids), the mixture was
heated to .about.126.degree. C. and added 356.5 g of citric acid.
The reaction maintained at 130.degree. C. for 2.3 hr as 29.7 g of
water was collected. The reaction product was further heated at
140.degree. C. for another 5 hr with N.sub.2 sparge, during which
time another 24.2 g of water was produced. The final product was
measured to have acid value of 0.589 meq/g, and amine value of
0.453 meq/g.
Example 2
TABLE-US-00001 [0053] TABLE 1 Preparation and Analytical Results of
Emulsifier 1 to 5 with Berolamine BA-20 Emulsifier 1 Emulsifier 2
Emulsifier 3 Emulsifier 4 Emulsifier 5 Type of Fatty Tall Oil Fatty
Tall Oil Fatty Century D1.sup.2 Nouracid RE09.sup.3 Nouracid
RE07.sup.3 Acid Acid.sup.1 Acid.sup.1 (Tall Oil Fatty (High Erucic
(Pure Erucic Acid) Rape Seed Acid) Acid) Type of Citric Acid
Acrylic Acid Citric Acid Citric Acid Citric Acid Carboxylic Acid
Amine content 0.386 1.28 0.453 0.622 0.306 of the final product
(meq/g) Acid content of 0.387 0.67 0.589 1.21 0.301 the final
product (meq/g) .sup.1commercial low rosin TOFA; .sup.2available
from Arizona Chemicals, USA; .sup.3available from Oleon GmbH,
Germany.
Example 3
Preparation of the Drilling Fluids of the Invention
[0054] The diesel based drilling fluids used in the following
non-limiting examples were prepared by mixing with 20 to 30 wt % of
base oils (#2 Diesel oil, or mineral oil, or synthetic alpha or
internal olefin), 0.3 to 3 wt % of the emulsifier, 0.3 to 1 wt % of
organoclay, 5 to 15 wt % of CaCl.sub.2 solution (25 wt % active),
and 50 to 70 wt % Barite (200 microns of top size) at 7000 to 12000
rpm for 30 to 90 min in a typical laboratory drilling fluid mixer.
No fluid loss or any other additives was used for the drilling
fluid preparation.
Example 4
Measuring Drilling Fluid Performance Properties
[0055] Drilling fluid rheology measurements were conducted using a
Fann 35A Viscometer with a R1-B1 concentric cylinder geometry at
120.degree. F. After measuring the viscosity @600 rpm (DR1), then
@300 (DR2), 200, 100, 6, and 3 rpm, the Plastic Viscosity and Yield
Point were calculated according to the following formulas:
Plastic Viscosity(PV)=DR1-DR2
Yield Point(YP)=2DR2-DR1.
[0056] Drilling fluid gel strength was measured for the viscosity
@3 rpm after a drilling fluid has set quiescently for a period of
time (10 seconds and 10 minutes) with unit of cP.
[0057] Drilling fluid Fluid Loss property was measured according to
the American Petroleum Institute (API) Recommended Practice 13B (RP
13B), 12.sup.th Ed (Sep. 1, 1988), on Section 3.4 of
High-Temperature/High-Pressure Filtration Test, p 11-13.
[0058] Drilling fluid emulsion stability measurement was conducted
using OFI Testing Equipment (Houston, Tex.) Emulsion Stability
Meter using a standard procedure.
[0059] The results of performance property tests are show in
Examples 5-11, FIGS. 1-2 and Tables 2-6.
Example 5
Example 6
TABLE-US-00002 [0060] TABLE 2 HTHP Performance of diesel based
drilling fluids (80/20 oil to water ratio) with the emulsifier
before aging at 300.degree. F./100 psi for 16 hrs Before Aging
Emulsifier 1 Emulsifier 2 Emulsifier 3 Emulsifier 4 (1.5 wt %) (2.6
wt %) (1.5 wt %) (2 wt %) Plastic 28 33 31 30 Viscosity (cP) Yield
Point 26.5 32.5 28.5 20 (lb/100 sq. ft) Electric 840 780 1045 920
Stability (v) Gel Strength 12/13 15/16 14/15 9/9 (10 s/10 min)
Example 7
TABLE-US-00003 [0061] TABLE 3 HTHP Performance of diesel based
drilling fluids (80/20 oil to water ratio) with the emulsifier
after aging at 300.degree. F./100 psi for 16 hrs After Aging
Emulsifier 1 Emulsifier 2 Emulsifier 3 Emulsifier 4 (1.5 wt %) (2.6
wt %) (1.5 wt %) (2 wt %) Plastic 30.5 56 30 31 Viscosity (cP)
Yield Point 5 50 19.5 29 (lb/100 sq. ft) Electric 538 660 818 1125
Stability (v) Gel Strength 4.5/5 21/23 10/10.5 13/14 (10 s/10 min)
Fluid Loss (ml) 8.4 12 3 3 (no water) (1 ml of (no water) (no
water) water)
Example 8
Example 9
TABLE-US-00004 [0062] TABLE 4 HTHP Performance of diesel based
drilling fluids (#2111-56) with 2.5 wt. % of the Emulsifier 5
before and after aging at 350.degree. F./160 psi for 16 hrs Before
Aging After Aging Plastic Viscosity (cP) 31 37 Yield Point (lb/100
sq. ft) 14 12 Electric Stability (v) 985 530 Gel Strength (10 s/10
min) 8/8.5 5.5/6 Fluid Loss (ml) 9.4 (no water)
Example 10
TABLE-US-00005 [0063] TABLE 5 HTHP Performance of mineral and
synthetic oil based drilling fluids (80/20 oil to water ratio) with
the Emulsifier 1 Before and after aging at 300.degree. F./100 psi
for 16 hrs Base synthetic oil: Base mineral oil: Isomerized alpha
olefin ODC oil.sup.4, with 16-18.sup.5, with 1.5 wt % 1.2 wt % of
Emulsifier 1 of Emulsifier 1 Before aging After aging Before aging
After aging Plastic 34 32.5 31 32.5 Viscosity (cP) Yield Point 7 9
14 17 (lb/100 sq. ft) Electric 827 587 1007 707 Stability (v) Gel
Strength 4/4 4/4 7/8 8/9 (10 s/10 min) Fluid Loss (ml) 5 6.4 (no
water) (no water) .sup.4available from Sasol North America;
.sup.5available from CP Chem, USA
Example 11
TABLE-US-00006 [0064] TABLE 6 Pour point of 65% of Emusifier 3 in
11.6% of mineral oil (LVT-200.sup.7) and 7.4% of additive Pour
Point (.degree. F.) Additive (ASTM D 97-57) Butyl Cellosolve.sup.6
35 Butyl Carbitol.sup.6 40 Butoxytriglycol.sup.6 40 Control (7.4%
of 60 LVT200.sup.7) .sup.6available from Dow Chemicals, USA;
.sup.7Available from ConocoPhillips, USA
* * * * *